security,rcu: Convert call_rcu(sel_netport_free) to kfree_rcu()

The rcu callback sel_netport_free() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(sel_netport_free).
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Paris <eparis@parisplace.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>

security/selinux/netport.c

@@ -67,22 +67,6 @@ static LIST_HEAD(sel_netport_list);
 static DEFINE_SPINLOCK(sel_netport_lock);
 static struct sel_netport_bkt sel_netport_hash[SEL_NETPORT_HASH_SIZE];
 
-/**
- * sel_netport_free - Frees a port entry
- * @p: the entry's RCU field
- *
- * Description:
- * This function is designed to be used as a callback to the call_rcu()
- * function so that memory allocated to a hash table port entry can be
- * released safely.
- *
- */
-static void sel_netport_free(struct rcu_head *p)
-{
-	struct sel_netport *port = container_of(p, struct sel_netport, rcu);
-	kfree(port);
-}
-
 /**
  * sel_netport_hashfn - Hashing function for the port table
  * @pnum: port number
@@ -142,7 +126,7 @@ static void sel_netport_insert(struct sel_netport *port)
 			rcu_dereference(sel_netport_hash[idx].list.prev),
 			struct sel_netport, list);
 		list_del_rcu(&tail->list);
-		call_rcu(&tail->rcu, sel_netport_free);
+		kfree_rcu(tail, rcu);
 	} else
 		sel_netport_hash[idx].size++;
 }
@@ -241,7 +225,7 @@ static void sel_netport_flush(void)
 		list_for_each_entry_safe(port, port_tmp,
 					 &sel_netport_hash[idx].list, list) {
 			list_del_rcu(&port->list);
-			call_rcu(&port->rcu, sel_netport_free);
+			kfree_rcu(port, rcu);
 		}
 		sel_netport_hash[idx].size = 0;
 	}